Electrical Insulator Casing

ABSTRACT

Systems, processes, and manufactures are provided that employ a casing associated with an electrical component to provide some, most, substantially all or all electrical insulative protection necessary for the electrical component. This casing may be further employed with potting or other materials to supplement and add additional or different protections for the component. These additional protections can include additional insulative resistance, thermal protection, moisture protection and other buffers to and from the environment.

BACKGROUND

The present invention relates to insulative casings that partially orfully insulate electrical components. In the present invention, theinsulative casings may serve to provide electrical insulativeresistance, thermal insulative resistance, reduced weight, or otherbenefits for electrical components associated with the casing.

When operating and performing their designed functions, printed circuitboards (PCBs) and other electrical components may be deployed andoperated in harsh environments. As protection, rigid metal boxes areoften used to protect the electrical components from moisture, heat, orother damaging environmental forces. In certain applications rigid metalboxes may also be used to protect electrical components from physicalloads, e.g., dynamic loads and static loads.

BRIEF SUMMARY

Embodiments of the invention include casings or other systems that mayserve to, among other things, buffer electrical components from theenvironment, dissipate heat, decrease weight, and provide electricalinsulation.

In embodiments, systems, processes, and manufactures are provided thatemploy a casing somehow associated with an electrical component toprovide some, most, substantially all, or all electrical insulativeprotection necessary for the electrical component. This casing may befurther employed with potting or other materials to supplement and adddifferent or additional protections for the component. These additionalor different protections can include additional insulative resistance,thermal protection, moisture protection, and other buffers to and fromthe environment.

In embodiments, use of a casing with electrical resistance may providefor use of potting and other materials previously disfavored or excludedfrom use with similar designs because the protections or buffersprovided by the potting or other material may be supplemented by thecasing and the material comprising it. In embodiments, the casing mayhave various configurations and features and may be used in conjunctionwith an enclosure having various configurations and features. Likewise,processes may employ either or both, and may vary when either or both acasing and an enclosure are employed.

Embodiments may include a power converter comprising a plurality ofelectrical components connected to a printed circuit board, an outerenclosure surrounding one or more of the electrical components, anelectrical insulative casing positioned between one or more of theelectrical components and the outer enclosure, the casing comprising apolymer or other nonmetallic material, and a potting material, whereinthe potting material may be positioned between the electrical insulativecasing and one or more of the electrical components. Still further, thepotting material in embodiments may be insufficient by itself to meetUnderwriter Laboratory requirements for insulative capacity, and theinsulative casing alone or in combination with the potting material maybe sufficient to meet or exceed Nationally Recognized Test Laboratories(NRTL) requirements for insulative capacity of electrical componentswithin the outer enclosure. These NRTLs may include UnderwritersLaboratory (UL), Canadian Standards Association (CSA), Interek, ETL,ANSI, ASTM, NFPA, NOM, and TUV standards and performance requirements.These NRTLs may vary by country and may vary by industry as well. Forexample, when renewable energy sources such as wind or solar are used inconjunction with the PCBs one set of standards may apply while adifferent or varied set of standards may apply when other components areconnected to the PCBs.

In embodiments the outer enclosure may have five or more sides, theprinted circuit board may comprise a solar photovoltaic modulemicroinverter having a DC input and an AC output, and the outerenclosure may have one or more thermal pads. In embodiments, the casingmay include a top having a full skyline or partial skyline profile,where the full skyline profile may mimic a profile of several electricalcomponents, and the partial skyline profile may mimic a profile of atleast one electrical component.

Still further details of embodiments include that the outer enclosuremay comprise a base with casing spacers, one or more thermal pads, andmeans for connecting the base with a cover, and wherein the base and acover may be sealable with a sealing gasket, and wherein a connectingmeans is outside of the perimeter of the sealing gasket. The outerenclosure may also include a cover with one or more domes, a sealingedge and a plurality of tabs, the sealing edge and plurality of tabspositioned to mate with the base when the outer enclosure is in a closedconfiguration.

Embodiments may also include processes that may include positioning aprinted circuit board within an electrical insulative casing;positioning the printed circuit board and insulative casing within anouter enclosure; and before or after each of the previous positioningsteps, deploying a potting material near and around electricalcomponents on the printed circuit board, the potting materialinsufficient by itself to provide the amount of electrical insulativeresistance necessary to satisfy NRTL electrical requirements for theprinted circuit board and electrical components. This process mayfurther include punching out a punchout on the insulative casing,placing a gasket between a top of the outer enclosure and a bottom ofthe outer enclosure, and securing the outer enclosure top to the outerenclosure bottom with fasteners positioned outside of the gasket and aseal created by the gasket mating with the outer enclosure top and theouter enclosure bottom.

Still further features and processes and embodiments may also bepossible. These embodiments, features, and related teachings areprovided throughout this disclosure. Moreover, it is to be understoodthat both the foregoing summary and the following detailed descriptionare exemplary and intended to provide further explanation withoutlimiting the scope of the invention as claimed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a side sectional view of an enclosure with an insulated shieldcasing and electrical components in accord with embodiments.

FIG. 2 is a side sectional view of an insulated shield casing andelectrical components in accord with embodiments.

FIG. 3 is a side sectional view of an insulated shield casing andelectrical components in accord with embodiments.

FIG. 4A is a top view of an enclosure top and an enclosure base inaccord with embodiments.

FIG. 4B is a top view of the reverse side of the enclosure top and theenclosure base from FIG. 4A in accord with embodiments.

FIG. 5 is an exploded perspective view of a cover assembly, electronics,and cabling in accord with embodiments.

FIG. 6 is a top view of an open enclosure including a bottom casing anda removed electronic printed circuit board in accord with embodiments.

FIG. 7 is a top view of an open enclosure with a top casing, a bottomcasing, and a printed circuit board between the two, in accord withembodiments.

FIG. 8 shows two partially assembled enclosures in accord withembodiments.

FIG. 9 shows an overhead view of insulated casings and sleeve shields inaccord with embodiments.

FIG. 10 shows a plan view of a cover assembly, electronics, and cablingmounted on a photo-voltaic module frame in accord with embodiments.

FIG. 11 shows process features as may be employed in accord withembodiments.

FIG. 12 shows process features as may be employed in accord withembodiments.

DETAILED DESCRIPTION

Embodiments include an enclosure or packaging with an insulative casingserving to provide electrical insulation for components within orassociated with the casing. The insulative casing may be used withpotting material and an outer enclosure to electrically insulate,protect, or dissipate heat from a printed circuit board or otherelectrical component. In embodiments, the electrical insulativeproperties of the casing may serve to reduce the use of potting materialor other electrical insulative materials and may also serve to increasethe selection of suitable potting material or other electricalinsulative materials. In other words, by using an insulative casing, theamount of other material and the suitable selection of other material,such as potting, used to protect or buffer the electrical component, maybe reduced as the casing can provide some or all of the requisiteelectrical insulation for the component.

Casings may have various features, may take various configurations, andmay be comprised of various materials. For example, casing embodimentsmay have one or more defined openings. These openings may be used foraccessing the components behind the casings, may be used duringmanufacture, may be used to transport thermal energy away from orthrough the casings, and may be used for other reasons as well.

Embodiments may be assembled by mounting a PCB to the base of an outerenclosure via standoffs of the enclosure base. In embodiments the outerenclosure may be aluminum, steel, rigid plastic, and various other rigidmaterials. A DC cable from a renewable energy source, having twoconductors (a plus and a minus), and an AC cable, having four conductors(line 1, line 2, neutral, and ground), may each be connected to the PCBand the enclosure using the standoffs. For the AC cable, the groundconductor may also be electrically coupled to the enclosure, serving toground the outer enclosure. For the DC cable, either wire may beconnected to the enclosure and, therefore, grounded.

In embodiments, during assembly, potting material may be injectedthrough a port or other opening in the enclosure, filling the voidsaround the PCB and around the components on the PCB. Once a sufficientamount of potting material is injected, the port or other opening mayremain or may be sealed. In embodiments, particularly hot components mayalso be thermally coupled to an outer enclosure through an opening orport in the casing. A thermal pad may be positioned with and traversethe opening or port such that an outer enclosure may serve as a heatsink.

Previously unfeasible potting material that was, for example, outside ofNRTL norms or criteria, may be selected in embodiments. Potting materialemployed in embodiments may be used to reduce, minimize, or preventmoisture from reaching the PCB, may be used for thermal dissipation, maybe used for additional electrical insulation, and may be used for otherreasons as well. In embodiments, suitable potting material may beselected after considering its properties and performance. For example,the selection of suitable potting materials may include passing certainreliability tests, such as “humidity-freeze” tests, where a PVmicroinverter is repetitively heated in a moist environment and thencooled well below freezing. This repeated loading and subsequentanalysis may be beneficial to determine if the potting is sufficient toretard or prevent meaningful moisture from being driven into theenclosure by temperature differentials. The testing and analysisperformed to select the potting material may also consider thermaldissipation properties of the potting material so that heat generated bycertain components may be spread across a larger area. In other words,material near the heat source may be selected based upon its ability todissipate or distribute heat from and about the components of a PCB.

In embodiments, various potting materials, including potting previouslydeemed inadequate, may be considered and used. For example, inembodiments, regulatory ratings for flame, temperature, insulation orother properties, from NRTLs, such as Underwriter's Laboratory, whichpreviously served to limit the number of suitable potting materials, mayno longer be applicable or may serve to exclude fewer potting materialsfrom being considered suitable for use. The increased number ofavailable potting material may allow selection and use of pottingmaterial previously disfavored or considered unavailable. This increasedrange of potting materials may include use of more flexible or lighterpotting material as well as potting material with a broader range ofsuitable thermal properties.

In embodiments, the properties of the potting material or its reducedvolume may each individually and cumulatively serve to reduce mechanicalforces on components touching the potting material. Cyclical stresses oninductor cores, solder joints, and larger components (such as filmcapacitors), which may be pried off the PCB, may also be reduced inembodiments.

Still further, embodiments may also include selection of pottingmaterial considering its viscosity. For example, more viscous pottingmaterials may be preferred as the material may have improved flow duringmanufacture or curing. Likewise, potting materials with improvedpreheating and flame rating limit characteristics may also be selected.

In embodiments, the outer enclosure may be designed such that a singleside, rather than two, may be mounted to a photovoltaic module frame.Also, the outer enclosure may have improved sealing designs such that atop and bottom cover have securements with reduced risk of compromisingthe seal between the top cover and the bottom cover. Also, in additionto solar microinverter applications, other renewable energy technologyapplications, such as wind, thermal, etc. may also benefit fromembodiments.

Still further, in embodiments, the casing may be configured to conformto the skyline of the circuit board. This variable surface may reducethe amount of potting material needed to cover targeted areas of thecircuit board or the entire circuit board. In other words, reducing andtailoring the space between the PCB and the casing, and the size anddimension and attributes of the casing, can serve to channel pottingmaterial flow and the amount of potting material needed to covertargeted areas of the PCB. In embodiments, the casing may be made fromvarious materials, including various polymers and plastics, and may beclear, translucent, and opaque.

In embodiments, certain designs may be targeted to substantiallydecrease the dependence of a PCB, such as a microinverter in an array ofphotovoltaic modules, on a specific type or types of potting material.Here and with other embodiments, design aspects may include using anencapsulated plastic casing that can be vacuum-formed to follow the“skyline” of the PCB components. Also, the base enclosure may be cast sothat features, such as heat sinks and standoffs, can be embedded in theenclosure itself. The enclosure base may comprise five of the six sidesneeded to complete the enclosure, forming an “open box” and the covercomponent may essentially be a flat metal plate in embodiments. Here andin other embodiments, the cover and base may be sealed through a gasket,such as an inexpensive gasket. Also, the cover and base may be fastenedtogether on the outer perimeter, so that few or none of the fastenerspenetrate the area inside the seal. Still further, in this and otherembodiments, the potting material may reside within the plastic casingand the enclosure may be a relatively long and narrow rectangle.

In preferred embodiments, the casing may be a polymer that can provideelectrical insulation between an outer metal enclosure and an internalPCB. As such, potting material employed no longer needs to have the samedegree of insulation resistance or flame ratings required for systemswithout the casing. In embodiments, the use of a casing may increase theavailable selection of suitable potting material. This increasedassortment of potting material may allow for reduced costs, lighterweights, less viscous potting materials, and more compliant (softer)potting materials. While other benefits may inure also, none of thesebenefits may be found in certain embodiments.

FIG. 1 shows a side sectional view of an electrical enclosure 100.Labeled in FIG. 1 is an outer enclosure base 120, a casing top 115 witha full skyline profile, and potting material 105 between the casing top115 and the other casing surfaces 190. Also labeled in FIG. 1 arevarious exposed and covered electrical components 110, spacer supports130 positioned beneath the casing surface 190, and a printed circuitboard 125. In this and other embodiments, the outer enclosure base 120may have a cover as well. This cover is not shown in FIG. 1.

In embodiments, and as shown in FIG. 1, the casing top 115 may have ahinge connector 140, connecting it to the other casing surface 190. Thishinge connector 140, an example of a connecting means, may allow thecasing top 115 to move away from the remaining casing surface 190, andmay also provide alignment during assembly. The hinge connector may be apermanent pivot point or a connection that can be connected anddisconnected. Various other connecting means, other than or in additionto the connecting hinge may also be used. These means include cup andball type systems, tab and receiving groove systems, coupled pivotingsystems, and pivoting systems that can be decoupled.

In embodiments, and as demonstrated in FIG. 1, the casing top or bottomor both, may fully mimic the skyline of the PCB and the electricalcomponents thereon. In so doing, potting material 105 placed within thecasing can be reduced because the cavity being filled is tailored. Asshown below, in addition to a full skyline profile, casing may alsopartially mimic the profile of the PCB or electrical components or maynot mimic the PCB or electrical component profile at all.

As noted earlier, the use of the casing around the printed circuit boardand its electrical components may help to reduce the amount of pottingmaterial needed to protect the printed circuit board and its electricalcomponents from freeze, thaw, moisture, and other environmental hazards.The casing may also provide sufficient or supplemental electricalresistance such that the amount of potting material may be reduced and alarger selection of potting material may be selected from. As can beseen, in embodiments, the potting material 105 may not be in contactwith the outer enclosure base 120. This absence of contact may serve toreduce the forces placed on the electrical components due to expansionand contraction of the potting material. In still further embodiments,the potting material may be outside of the casing as well, and may alsobe in contact with one or more surfaces of the outer enclosure. Inpreferred embodiments, however, contact with the potting material andthe outer enclosure may be minimized or eliminated.

As can also be seen, in embodiments, spacer supports may be present onone or more surfaces of the enclosure 120. These spacer supports 130 mayhelp align and position the casing, printed circuit board, andelectrical components within the enclosure 120. The spacer supports 130may be uniformly positioned, may be nonuniformly positioned, and may bepositioned at various locations in order to properly support, secure,and align components within the enclosure 120.

As can also be seen in FIG. 1, the potting material 105 may completelyor substantially fill the space within the casing. In other embodiments,potting material may not completely fill the space such that voids orgaps may exist between the potting material and the casing material.And, in preferred embodiments, little if any potting material will beplaced or expand outside of the casing after placement. As can befurther seen in FIG. 1, certain fragile components, such as inductors,diodes, thin-film capacitors, and resistors, which lack packaging orhave exposed leads, may themselves be completely surrounded by thepotting material such that leads from these components may not onlyreceive thermal insulation from the potting material but may alsoreceive structural support and cushioning from the potting material aswell.

Space beyond the case and within the cover may accommodate thermalexpansion and contraction of the potting material without offeringresistive forces sufficient to damage electrical components or a PCBwithin the potting material. In embodiments, thermal pads may beemployed to transport heat from a heat generating component, through thecasing, and to the outer enclosure. These thermal pads may be formed onthe outer enclosure and may be added as well. In each instance, theouter enclosure may serve as a heat-sink for the heat generatingcomponents. In embodiments, potting material may also serve todistribute and dissipate thermal energy from heat generating components.In addition, the thermal distributive and conductive properties of thepotting may be better or substantially better than those properties ofthe casing. Still further, when materials are selected in embodiments,they may be selected such that thermal dissipation required for thesystem may be partially satisfied, substantially satisfied, or fullysatisfied by the potting or the potting and the outer casing and theelectrical insulative properties may be partially satisfied,substantially satisfied, or fully satisfied by the casing.

FIG. 2 shows a side sectional view of the casing surrounding a printedcircuit board in accord with embodiments. As can be seen in FIG. 2, thecasing top surface 215 is connected to the casing bottom surface 290with connectors or connecting means 245. These connectors or connectingmeans 245 permit the casing top surface 215 to be completely removedfrom the casing bottom surface 290 during assembly, and, in someembodiments, afterwards as well. Also labeled in FIG. 2 are ports 235,electrical components 110, printed circuit board 125, cable 210, andpotting material surface 205. As can also be seen in FIG. 2, the pottingmaterial may not completely fill the space within the casing. Forexample, the potting material surface 205, which is lower than thecasing top surface 215, demonstrates how potting material voids mayexist within the casing.

During assembly, potting material may be injected through the ports 235in order to fill spaces in and around the printed circuit board 125 andthe components 110 positioned thereon. In embodiments, potting materialmay also be deposited with the top in an open position by placingpotting material under, on and around the printed circuit board and theelectrical components and then finishing the deployment of the pottingmaterial after the casing top surface is in place and in its finalposition. The connectors 245 may allow for alignment, as well assecurement, and may be a permanent as well as a removable connectiontype. The ports 235 may be temporary and or permanent, and may have flowblocking means 236 serving to prevent multi-directional flow of pottingthrough the port and outside of the casing during or after assembly. Inother words, the flow blocking means 236 may provide for flow of pottingmaterial into the casing but retard its flow out of the casing. Thisflow blocking means 236 may comprise a scored opening or more elaboratedesigns, such as a valve.

As can also be seen in FIG. 2, in embodiments, the cable 210 may providefor connections to and from the printed circuit board and itscomponents. As can also be seen, port 235 through which the cable 210passes may be sized and positioned such that moisture and other externalcomponents may be unable to enter the casing once the cable 210 is inposition. In addition, the potting material placed on the inside of thecasing may further serve to prevent moisture from entering and coming incontact with the various components of the PCB.

FIG. 3 shows another embodiment in which the casing surrounds a printedcircuit board having components in a potting material 105 placed in andaround the electrical components 110. FIG. 3 shows a connecting meanshaving an upper socket connector 245 and a lower ball connector 350along external surfaces of the casing. These connectors can provide forthe attachment between the top surface casing 315 and the bottom casingsurface 390. FIG. 3 also shows a potting material 105, a pottingmaterial surface 205, and exposed electrical components 110.

As can be seen in FIG. 3, and as discussed above, the exposed electricalcomponents 110 may be present on both the top and bottom of the printedcircuit board 125 during assembly. Potting material may be placed in andaround electrical components and a printed circuit board and may notcompletely fill the space within the casing. Moreover, the casingsurface may not provide a full skyline as in FIG. 1 or partial skylineas in FIG. 2, but may, instead, simply be a substantially or fullyplanar surface as shown in FIG. 3.

As can also be seen in FIG. 3, a void 316 may exist between the pottingmaterial surface 205 and the casing top surface 315. In embodiments, andas shown in FIG. 3, a cured potting material surface may be a roughsurface that varies over the printed circuit board 125 and may besufficiently thick to simply cover the components in the printed circuitboard to a minimum, but not necessarily a consistent thickness. Theminimum may be set to provide adequate environmental protections,including thermal protection and moisture protection. In embodiments,the viscosity of the potting material before curing may influence theprofile and thickness of the finally cured potting material. When highviscosity potting materials are selected it may be preferable inembodiments to use curing forms to control the thickness of the curedpotting material by retarding its propensity to flow and self-levelduring curing.

FIG. 4A and FIG. 4B show outer enclosure top 455 and outer enclosurebase 420. FIG. 4A shows one side of the outer enclosure top 455 and theouter enclosure base 420 while FIG. 4B shows the other side of the sameouter enclosure top 455 and outer enclosure base 420. Visible in FIG. 4Ais a port 460, a sealing seat 475, and connector openings 480 of theouter enclosure top 455. Also visible in FIG. 4A are connectorreceptacles 465, port 435, alignment spacer 430, and sealing seat 470 ofthe outer enclosure base 420. The edge connector, connector openings,and connector receptacles may serve as a connection means inembodiments. Visible in FIG. 4B on the outer enclosure top 455 are port460, sealing seat 475, edge connector 445, and connector openings 480.Also visible in FIG. 4B on the outer enclosure base 420 are connectorreceptacles 465, and receptacle edge connector 446. The port 460 isshown without a flow blocking means as may be employed in embodiments.

As can be seen in the figures, the means of connecting the top to thebase may be positioned outside of the sealing surfaces. This may be doneto reduce the likelihood of piercing the sealing surfaces and also topromote better seal between the top and base. For example, inembodiments, the edge connector 445 may hook onto and below thereceptacle edge connector 446 of the base 420. On the opposite edge ofthe top, the edge with the connector openings 480 may pull down throughthe connector openings 480 into the connector receptacles 465 to securethe top 445 to the base 420 and to compress or otherwise seal thesealing seat 470 and 475.

As can be seen in FIG. 4A, the spacing of the connector receptacles 465may not be uniform and the spacing of the alignment spacers 430 may beuniform. The converse may also be true in embodiments. As can also beseen in FIG. 4A, ports 435 may exist on both sides of the enclosure base420 such that cabling can be connected to a printed circuit board orelectrical components within the base from both sides. Likewise, a port460 may also exist in the enclosure top 455. Still further, inembodiments, various other ports may also exist in addition to or ratherthan the ports shown in the figures herein. Also, as shown, inembodiments, the top and base of the enclosure may be mated by screwsthat are outside of a gasket, such that the mechanical coupling formedat the screws need not be watertight. Also, in embodiments, theenclosure may be designed so that fewer edges need to be fastened withscrews or other additional fasteners.

The base of outer enclosure may be cast or molded such that additionalfeatures, such as post holes and heat sinks 421, may also be readilyadded. The enclosure top may be fully removable or hinged such that itmay be readily opened and closed. In embodiments, the enclosure top maybehave as a “pizza box” top, with the top, coupled to the bottom, beingable to lay flat in an open position and being secured in a closedposition.

In embodiments, the gasket and sealing seat may provide some,substantial, most, or all of the needed moisture protection for theelectrical components in the enclosure. As noted, the fasteners may bepositioned on the outer periphery of the enclosure so that the risk ofleakage through the fasteners is reduced. The properties and resilienceof a sealing gasket positioned around the top and the base may addfurther sealing integrity and may supplement the sealing provided bypotting material.

In embodiments, an “open-box” design, as is shown in FIGS. 4A and 4B,may provide that the PCB and a portion of the casing can be mountedtogether before applying the potting material and placing the componentsin the enclosure. With the cover removed, the potting material may bepoured over the PCB and into the plastic casing until filled. Inembodiments, a higher viscosity potting material may be selected suchthat the potting material may readily flow around electrical components,forming a void-free seal, at room or minimally elevated temperatures.The casing may then be further assembled, now with the potting materialwithin it. When a partial or full skyline design is used for the casing,the size and number of empty voids in the casing may be limited and thenecessary volume of potting material required may be reduced as well. Inembodiments, vertical ridges on the metal cover may be used for seatingthe case as well.

Still further, in embodiments, ridge-like features may be added to theenclosure base lower edge. These features may be drilled/tapped so thatusers can add more features, such as hooks, clasps, shells, cablemanagement systems, etc.

FIG. 5 shows an exploded isometric view of a cover assembly, electronicsand cabling 500 in accord with embodiments. As can be seen in FIG. 5, anouter enclosure top 555 may be coupled to an outer enclosure base 520,and various components may be positioned between and within this top andbase.

Visible in FIG. 5 are connector screws 501, cover domes 556, an ACjunction assembly 503, AC connectors 507, an insulated shield casing top515, DC connectors 504, sleeves for magnetic components 506, a printedcircuit board with exposed electrical components 525, a casing bottom590, thermal pads 591-593, a sealing seat 570, multiple alignmentspacers 530, and multiple structural reinforcement contours 594.

In embodiments, and as shown in FIG. 5, the casing bottom 590 and thecasing top 515 may surround and protect the printed circuit board 525and the various components atop the printed circuit board, below theprinted circuit board, and connected to the printed circuit board. Ascan be seen, the casing top 515 shown in FIG. 5 is a flat profile andnot a skyline profile as shown in FIG. 1, or a semi-skyline profile asshown in FIG. 2. As also shown in FIG. 5, and in embodiments, theconnector screws 501 may secure the printed circuit board 525 to theouter enclosure base 520 and may also secure the outer enclosure cover555 to the base 520.

During assembly, potting material may be placed in and around theprinted circuit board 525. This may be done through the ports from abovethe printed circuit board during assembly, and through other methods andopenings as well. The dome 556 of the enclosure cover 555 may allow forexpansion and contraction of the casing top 515. This expansion andcontraction may be preferred in order to reduce, minimize, or eliminateexpansion and contraction forces from being placed on the printedcircuit board 525 and the exposed electrical components located thereon.

FIG. 6 and FIG. 7 show a partially assembled cover assembly,electronics, and cabling in accord with embodiments. FIG. 6 shows anenclosure cover connected along an edge to the base, with cable sleeves761 and 762 attached. Also visible in FIG. 6 is the printed circuitboard and thermal transfer pads 622 of the casing 590.

During assembly the printed circuit board may be positioned within thecasing 590 such that the thermal transfer pads 622 may be in contactwith the printed circuit board or components thereon in order to allowheat to be drawn away from the printed circuit board and onto the casingduring operation of the electrical components. The gasket seat or gasketridge 521 may accept a gasket and together may serve as a sealingsurface to prevent moisture or other environmental contaminants fromentering the sealed assembly.

In FIG. 7, the printed circuit board and the casing top 515 have beeninserted into the base. Also labeled in FIG. 7 is the connector opening480, the port 460, and cable sleeves 762 and 761. As can be seen in FIG.7, prior to closing the cover and sealing it down, the port 460 mayalign with an opening in the casing top 515, and the casing top 515 maybe seated near or directly against the gasket seat or gasket ridge 521.During assembly, prior to or after the closure of the cover of FIG. 7potting material may be added in and around electronics the printedcircuit board.

FIG. 8 shows an embodiment with electronics before and after beingcovered with a casing top 515. The embodiment with electronics 800 isshown without the casing top, while the embodiment with electronics 831is shown with the casing top 515. As shown in FIG. 8, in embodiments,the ports entering and exiting the casing and the enclosure may not beopposite each other but may be in various positions. For example, shownwith the assembly 800, the DC connector 504 enters the side of the casein the side of the enclosure through a unified sleeveless connector 863,while the AC connection to the printed circuit board is made to an endof the PCB, and an end of the case, and an end of the enclosure.

Also visible in FIG. 8 are the structural reinforcement contours 594,the sealing seat 570, and the edge connector receptacles 802. Thus, inembodiments, the combination of the edge connector receptacle 802 andthe sealing seat 570, together an example of a connection means, mayserve to prevent moisture or other environmental contaminants fromentering into the casing or the enclosure when in a closed position.Also, as can be seen in FIG. 8, the casing top 515 need not have a portor other opening in embodiments.

FIG. 9 shows a plan view of a casing top 515, casing bottom 590, sleeve761 and sleeve 762 in accord with embodiments. A tiered dome 1016 isshown on the casing top 515. Also visible is a casing port punch-out1017, and casing sealing edge 1018. The sleeves 761 and 762 are shown asangled sleeves with various contours and recesses to accommodate cablingand provide sealing with the cabling and the enclosure and casing. Thecasing port punch-out may be removed during assembly to provide forpotting placement, for thermal transport through the casing, and forother reasons as well.

FIG. 10 shows a plan view of a cover assembly, electronics, and cablingassembly 500 attached to a mounting frame 1000 of a photovoltaic modulein accord with embodiments. Screw connectors 1011 are shown through themounting frame 1000 into the cover assembly, electronics and cablingassembly 500. Also visible in FIG. 10 are the DC connector 540, and theAC junction assembly 503. In embodiments, solar panel microinverters mayneed to be accommodated in size and coupling methods to specificphotovoltaic (PV) frames, which can vary by PV manufacturer. Forexample, in this embodiment, a long edge is the predominant mountingsurface. In embodiments, this long edge can be further adapted tocoincide with different manufacturers' PV frames.

FIG. 11 shows the flow of a process as may be employed in accord withembodiments. As shown at 1100, an insulated shield casing may be alignedwith exposed electrical circuits to be protected and insulated; and asshown at 1110, a potting material may be placed around the components ofthe exposed electrical circuit to be shielded. During placement or onceplaced, as shown at 1120, the assembly of the insulated shield and theprotection of the enclosure may continue. These process embodiments mayemploy some of the various features taught throughout this application.These features may be combined from the various figures embodiments andmay be combined in various and still different ways.

FIG. 12 shows a process as may be employed in various ways inembodiments. As with FIG. 11, features and steps of this process may beformed in various orders and may be conducted with more or lessactivity. Likewise, components described throughout may be used orassembled in various ways and with other components.

As shown in FIG. 12, processes may start at 1210. At 1220, pottingmaterial may be poured into an open casing on a level surface, firstunderneath the printed circuit board and, when the potting materialrises above the board, at 1230, atop the board by moving a nozzledispensing the potting to an open space on the board. As shown at 1240,confirmation that the potting material covers all the components may bemade and the potting material poured over the printed circuit board maybe measured. In embodiments, 423 ml of potting material may be a targetmeasure, but in embodiments, depending upon the casing dimensions, andthe dimensions of the PCB and the properties of the potting material andthe casing, other target volumes of dispensed potting may also be used.These target volumes may include ranges of fill from less than half tonear or at 100% percent potting fill. The targeted volume of dispensedpotting and the targeted percentage potting fill may depend on thepotting material being used, on the size of the printed circuit boardsand electrical components, the spacing between the printed circuit boardand the casing, and on other variables and considerations as well.

At 1250, the potting may be allowed to cure for a period of time, forexample, 15 to 20 minutes on a level surface. This curing may beaccelerated by the addition of heat, radiation, or the use of some otherkind of accelerant. At 1260, the assembly may return to another step,here shown as Functional Verification Testing 2 (FVT2). This FTV2 may bethe second functional testing of the components to verify their properfunction. As shown at 1270, curing may occur at a target temperature,here 25° C., for a determined period of time, such as 10 to 12 hours.Other features and different features and steps may be performed aswell. Once sealed in potting, however, if the component fails the FVT2,repair may not be possible and component may need to be discarded. 1280shows an end to the assembly.

In preferred embodiments the potting material may exhibit a viscosity of7000 cp or lower @25° C., have a hardness of 70 avg Shore A, and exhibita coefficient of thermal expansion of 190 ppm or lower. These propertiesfor the potting material are not limiting as potting material inembodiments may exhibit other properties, even higher ones, forviscosity, hardness, and thermal expansion as well.

Still further, in embodiments, the potting material may have a lowviscosity to assist in pouring the potting material. The pottingmaterial may also be selected to minimize thermal forces on theelectronic components. Here a low coefficient of thermal expansion forthe potting material can provide for a higher Shore A while a highercoefficient of thermal expansion may provide for a needed lower Shore Ahardness. An Epic Resin S7302-01 may be used as a potting material inembodiments. Other particulars of this potting material include aviscosity of 2500-3500 cps, a Shore A hardness of 68-72, a CTE(175-190)10⁻⁶ 1/C, a cure time of 10-12 hours @25° C., a gel time of15-25 minutes, an RTI of 50° C. and a TG of −50° C.

In embodiments, the use of casing may eliminate or greatly increase theUL requirement of having a Relative Temperature Index of a certainscore. For example, past limits of 90° C. may be greatly increased oreliminated altogether in embodiments.

In embodiments, the potting material may have a working life of 15minutes or more and may comprise an epoxy/amine with various colors,including: clear, black, white, and other colors. In embodiments, curingmay require elevated temperatures, the introduction of radiation, or theuse of other accelerant techniques.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an” and “the” are intended toinclude plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specific to thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operation, elements,components, and/or groups thereof.

Embodiments may also be implemented as a computer process, a computingsystem or as an article of manufacture such as a computer programproduct of computer readable media. The computer program product may bea computer storage medium readable by a computer system and encodingcomputer program instructions for executing a computer process.

The corresponding structures, material, acts, and equivalents of allmeans or steps plus function elements in the claims below are intendedto include any structure, material or act for performing the function incombination with other claimed elements as specifically claimed. Theforegoing description has been presented for purposes of illustrationand description, but is not intended to be exhaustive or limited to theinvention in the form disclosed. Many modifications and variations maybe done without departing from the scope and spirit of the invention.The embodiment was chosen and described in order to best explain theprinciples of the invention and the practical application, and to enableothers of ordinary skill in the art to understand the invention forembodiments with various modifications as are suited to the particularuse contemplated.

1.-19. (canceled)
 20. An electrical enclosure comprising: a rigidweatherproof outer enclosure; an electrical insulative casing positionedwithin the rigid weatherproof outer enclosure and surrounding a printedcircuit board (PCB) having an upper surface and a lower surface; and apotting material, the potting material previously flowed into the casingand around the PCB, the potting material covering both the upper surfaceof the PCB and the lower surface of the PCB.
 21. The electricalenclosure of claim 20 wherein the casing is completely encased by therigid weatherproof outer enclosure and wherein the PCB is configured toreceive a dc voltage from a photovoltaic cell.
 22. The electricalenclosure of claim 20 wherein the casing comprises one or more ports,the ports providing access to electrical components of the PCB when theelectrical enclosure is fully assembled, or to potting material flowduring assembly of the electrical enclosure, or both.
 23. The electricalenclosure of claim 20 wherein the casing mimics a partial skyline or afull skyline of the upper surface of the PCB or the lower surface of thePCB or both surfaces of the PCB, wherein the potting material fills themajority of the space within the casing and surrounds all exposedcomponents of the PCB and surrounds the entirety of the upper surface ofthe PCB and the lower surface of the PCB, and wherein the pottingmaterial is curable.
 24. The electrical enclosure of claim 20 whereinthe casing has a lid and one or more additional sections, the lid andthe one or more additional sections surrounding the PCB.
 25. Theelectrical enclosure of claim 20 wherein the potting material has amounded shape over the entire upper surface of the PCB or the PCBcomprises a solar photovoltaic module microinverter having a DC inputand an AC output or both the mounded shape and the DC input and ACoutput.
 26. The electrical enclosure of claim 20 further comprising: acable sleeve penetrating through casing and the enclosure, providing aweatherproof seal, and configured to permit cable access to the PCB fromoutside the enclosure.
 27. The electrical enclosure of claim 20 whereinthe potting material is insufficient to meet one or more publishedrequirements for electrical insulative capacity and wherein the casingalone or in combination with the potting material is sufficient to meetor exceed one or more published requirements for electrical insulativecapacity of electrical components within the outer enclosure.
 28. Aprocess for assembling an electrical component enclosure, the processcomprising: surrounding a printed circuit board (PCB) with an electricalinsulative casing and a weatherproof outer enclosure; and flowingpotting material near and around electrical components on an uppersurface of the PCB and a lower surface of the PCB, the potting materialinsufficient by itself to provide the amount of electrical insulativeresistance necessary to satisfy one or more previously publishedelectrical requirements for the printed circuit board and its electricalcomponents, wherein the electrical insulative casing comprises one ormore ports, the ports providing access to electrical components when theelectrical insulative casing is fully assembled or to potting materialflow during assembly of the electrical insulative casing or both. 29.The process of claim 29 wherein the PCB is configured to receive a DCvoltage from a photovoltaic and modify that received voltage to be anoutput of the PCB.
 30. The process of claim 29 further comprising:curing the potting material with at least heat or light, and wherein theelectrical insulative casing includes a skyline profile mimickingelectrical components on at least one surface of the PCB.
 31. Theprocess of claim 29 wherein potting material is flowed through one ormore ports in the electrical insulative casing.
 32. The process of claim29 wherein subsequent to flowing the potting material, allowing thepotting material to cover all components on the PCB.
 33. The process ofclaim 29 further comprising: thermally coupling one or more componentsof the PCB through the electrical insulative casing and to the outerenclosure.
 34. The process of claim 29 wherein the potting material isinsufficient to meet one or more published requirements for electricalinsulative capacity and wherein the casing alone or in combination withthe potting material is sufficient to meet or exceed one or morepublished requirements for electrical insulative capacity of electricalcomponents within the outer enclosure.
 35. The process of claim 29wherein one or more thermally conductive pads serve to dissipate thermalenergy from one or components of the PCB to the outer enclosure.